From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5482AC9830E for ; Fri, 25 Sep 2026 10:30:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E833010F9D3; Fri, 25 Sep 2026 10:30:12 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="JKJvy+7s"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.21]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8C5BA10F9CA; Fri, 25 Sep 2026 10:30:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1790332212; x=1821868212; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=tdIAs/dpz2Z7UVtdZSYRgTG6F9dIY1PgsnpQndrYA2k=; b=JKJvy+7sSXwoK3U/QNi9uHdvUr3Ax6qG2HzXf+aldyCh7Q3WASFjnpFL xloT8UeSF/dbdikA652X7b0jeVy6O3Hhb9wF6foo1uboeGuAPXNjiRk0s 5OIYTZ+gTqandGOan1gVI6m7roaGuysiSIkh9Nrgful4L8Nt8VmMSs8tS xPPSK7KdttE8bVkilFBd7RZYEWQglApm3L4Olt17F+rDoxGPufaSnGJBk bJjxpwnmbIOj6Q1t++qcilRJqSh2DwZA+hkhe7B4V81a0ad+mMnDRzKQz 1tiG37XUOYkOcOPRMTd9c63A4RRvgZEe5IlfN4CdLGXY7DK2Lmm8mTII0 A==; X-CSE-ConnectionGUID: UR7eBNs/Rsm0n+OMjhyyVQ== X-CSE-MsgGUID: 7xZdEy0vQYyz9wgP+6lNlA== X-IronPort-AV: E=McAfee;i="6800,10657,11915"; a="89980006" X-IronPort-AV: E=Sophos;i="6.27,122,1787036400"; d="scan'208";a="89980006" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by orvoesa113.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Sep 2026 03:30:12 -0700 X-CSE-ConnectionGUID: 2IA90UGXSJqO3TvnE5veVg== X-CSE-MsgGUID: YKi5sfdcSWqclw08ZF67uQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,122,1787036400"; d="scan'208";a="274393514" Received: from smoticic-mobl1.ger.corp.intel.com (HELO localhost) ([10.245.245.90]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Sep 2026 03:30:09 -0700 From: Jani Nikula To: Naladala Ramanaidu , intel-xe@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Cc: ankit.k.nautiyal@intel.com, Naladala Ramanaidu Subject: Re: [PATCH v2 1/1] drm/i915/gmbus: Add bit-banging debugfs control In-Reply-To: <20260924152812.439986-2-ramanaidu.naladala@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs Bertel Jungin Aukio 5, 02600 Espoo, Finland References: <20260924152812.439986-1-ramanaidu.naladala@intel.com> <20260924152812.439986-2-ramanaidu.naladala@intel.com> Date: Fri, 25 Sep 2026 13:30:06 +0300 Message-ID: MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Thu, 24 Sep 2026, Naladala Ramanaidu wrote: > Add a connector debugfs interface to enable or disable I2C > bit-banging for Intel GMBUS adapters. > > v1: Address below review comments: (Jani Nikula) > - Remove HDMI-specific EDID read path changes. > - Control bit-banging directly from debugfs via intel_gmbus_force_bit() > > Assisted-by: OpenAI Codex:GPT-5 > Signed-off-by: Naladala Ramanaidu > --- > .../drm/i915/display/intel_display_debugfs.c | 3 + > .../drm/i915/display/intel_display_types.h | 1 + > drivers/gpu/drm/i915/display/intel_gmbus.c | 61 +++++++++++++++++++ > drivers/gpu/drm/i915/display/intel_gmbus.h | 3 + > 4 files changed, 68 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c > index 3e302f23f247..74f065175a72 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c > +++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c > @@ -40,6 +40,7 @@ > #include "intel_fb.h" > #include "intel_fbc.h" > #include "intel_fbdev.h" > +#include "intel_gmbus.h" > #include "intel_hdcp.h" > #include "intel_hdmi.h" > #include "intel_hotplug.h" > @@ -1327,6 +1328,8 @@ void intel_connector_debugfs_add(struct intel_connector *connector) > if (!root) > return; > > + intel_gmbus_connector_debugfs_add(connector); > + Superfluous newline. All the other calls below are back to back. > intel_drrs_connector_debugfs_add(connector); > intel_hdcp_connector_debugfs_add(connector); > intel_pps_connector_debugfs_add(connector); > diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h > index 79f30660c2b6..5cef2582c361 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_types.h > +++ b/drivers/gpu/drm/i915/display/intel_display_types.h > @@ -558,6 +558,7 @@ struct intel_connector { > u8 polled; > > int force_joined_pipes; > + bool force_bit_banging; This should be hidden in struct intel_gmbus next to force_bit, maybe as debugfs_force_bit or something. > > struct { > struct drm_dp_aux *dsc_decompression_aux; > diff --git a/drivers/gpu/drm/i915/display/intel_gmbus.c b/drivers/gpu/drm/i915/display/intel_gmbus.c > index 60a70dea5d85..38d6d1148399 100644 > --- a/drivers/gpu/drm/i915/display/intel_gmbus.c > +++ b/drivers/gpu/drm/i915/display/intel_gmbus.c > @@ -27,6 +27,7 @@ > * Chris Wilson > */ > > +#include > #include > #include > #include > @@ -871,6 +872,66 @@ static const struct i2c_algorithm gmbus_algorithm = { > .functionality = gmbus_func > }; > > +bool intel_gmbus_is_adapter(struct i2c_adapter *adapter) This should be static. > +{ > + return adapter->algo == &gmbus_algorithm; > +} > + > +static int intel_force_bit_banging_show(struct seq_file *m, void *data) > +{ > + struct intel_connector *connector = m->private; > + > + seq_printf(m, "%u\n", connector->force_bit_banging); > + > + return 0; > +} > + > +static ssize_t intel_force_bit_banging_write(struct file *file, > + const char __user *ubuf, > + size_t len, loff_t *offp) > +{ > + struct seq_file *m = file->private_data; > + struct intel_connector *connector = m->private; > + bool force_bit_banging; > + int ret; > + > + ret = kstrtobool_from_user(ubuf, len, &force_bit_banging); > + if (ret) > + return ret; > + > + if (force_bit_banging != connector->force_bit_banging) { > + intel_gmbus_force_bit(connector->base.ddc, force_bit_banging); > + connector->force_bit_banging = force_bit_banging; > + } > + > + *offp += len; > + > + return len; > +} > + > +static int intel_force_bit_banging_open(struct inode *inode, struct file *file) > +{ > + return single_open(file, intel_force_bit_banging_show, inode->i_private); > +} > + > +static const struct file_operations intel_force_bit_banging_fops = { > + .owner = THIS_MODULE, > + .open = intel_force_bit_banging_open, > + .read = seq_read, > + .llseek = seq_lseek, > + .release = single_release, > + .write = intel_force_bit_banging_write, > +}; > + > +void intel_gmbus_connector_debugfs_add(struct intel_connector *connector) > +{ > + if (connector->base.ddc && > + intel_gmbus_is_adapter(connector->base.ddc)) The connector->base.ddc != NULL check should be inside intel_gmbus_is_adapter(). > + debugfs_create_file("intel_force_bit_banging", 0644, > + connector->base.debugfs_entry, connector, > + &intel_force_bit_banging_fops); > +} > + > static void gmbus_lock_bus(struct i2c_adapter *adapter, > unsigned int flags) > { > diff --git a/drivers/gpu/drm/i915/display/intel_gmbus.h b/drivers/gpu/drm/i915/display/intel_gmbus.h > index 5fdeab1aa794..968f8cb42821 100644 > --- a/drivers/gpu/drm/i915/display/intel_gmbus.h > +++ b/drivers/gpu/drm/i915/display/intel_gmbus.h > @@ -9,6 +9,7 @@ > #include > > struct i2c_adapter; > +struct intel_connector; > struct intel_display; > > #define GMBUS_PIN_DISABLED 0 > @@ -41,6 +42,8 @@ int intel_gmbus_output_aksv(struct i2c_adapter *adapter); > > struct i2c_adapter * > intel_gmbus_get_adapter(struct intel_display *display, unsigned int pin); > +bool intel_gmbus_is_adapter(struct i2c_adapter *adapter); > +void intel_gmbus_connector_debugfs_add(struct intel_connector *connector); > void intel_gmbus_force_bit(struct i2c_adapter *adapter, bool force_bit); > bool intel_gmbus_is_forced_bit(struct i2c_adapter *adapter); > void intel_gmbus_reset(struct intel_display *display); -- Jani Nikula, Intel